K21

⚠ Non-billable (Header)

Gastro-esophageal reflux disease

Diseases of the digestive system (K00-K95)

⚠️ This is a category header code — not billable. Use a more specific child code below.

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❌ Excludes1

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These codes are mutually exclusive. Never code them together.

• newborn esophageal reflux (P78.83)

Child Codes (2)

K21.0Gastro-esophageal reflux disease with esophagitisHeader K21.9Gastro-esophageal reflux disease without esophagitis✓ Billable

Clinical Description

ICD-10-CM code K21 represents gastro-esophageal reflux disease. This code falls under the Diseases of the digestive system (K00-K95) classification. It is a non-billable category header code. A more specific child code from the list below must be used for billing and reimbursement purposes.

Frequently Asked Questions

What is ICD-10 code K21?

ICD-10-CM code K21 is "Gastro-esophageal reflux disease". It belongs to the category: Diseases of the digestive system (K00-K95).

Is K21 a billable ICD-10 code?

No, K21 is a non-billable header code. A more specific child code must be used for billing.

What codes are excluded with K21?

K21 has 1 Excludes1 rule(s). These codes are mutually exclusive and cannot be coded together on the same claim.

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Code Information

CodeK21

BillableNo — Header code

CategoryDiseases of the digestive system (K00-K95)

Excludes11 rule(s)

Excludes20 note(s)

Child codes2

Data Source

CMS ICD-10-CM 2026 Tabular List

Updated October 1, 2025 (FY2026)